Pizzari Tania, Wickham James, Balster Simon, Ganderton Charlotte, Watson Lyn
Lower Extremity & Gait Studies Research Group, Australia; Department of Physiotherapy, La Trobe University, Victoria, Australia.
School of Biomedical Science, Charles Sturt University, NSW, Australia.
Clin Biomech (Bristol). 2014 Feb;29(2):201-5. doi: 10.1016/j.clinbiomech.2013.11.011. Epub 2013 Nov 26.
Scapular dyskinesis, characterised by drooping scapulae and reduced upward rotation, has been implicated in the presentation of a number of shoulder disorders. Traditionally, in shoulder rehabilitation programmes, the shrug exercise has been prescribed to facilitate upward rotation of the scapula by strengthening the upper trapezius muscle. The aim of this research was to compare muscle activation levels during the standard shrug and the upward rotation shrug in a normal and pathological population.
Surface electrodes recorded electromyographical activity from upper trapezius, middle trapezius, lower trapezius and serratus anterior muscles in 23 normal participants and 14 participants with multi-directional shoulder instability. Participants completed 10 trials of the standard shrug exercise at 0° of shoulder abduction and the upward rotation shrug exercise at 30° of shoulder abduction in the coronal plane. Muscle activity was expressed as a percentage of maximum voluntary isometric contraction.
The four muscles tested performed at a higher intensity during the modified shrug than the standard shrug. Upper trapezius and lower trapezius activity was significantly greater (P < 0.05) in both populations. Though for middle trapezius and serratus anterior muscles, the modified shrug was statistically significant only in the normal population, P = 0.031 and P = <0.001 respectively.
The upward rotation shrug is a more effective exercise for eliciting muscle activity of the upper and lower trapezius than the standard shrug in a normal and multi-directional instability population. Clinically, the upward rotation shrug might be useful to address scapular dyskinesis involving drooping shoulders and reduced scapula upward rotation.
肩胛运动障碍的特征为肩胛骨下垂和上旋减少，与多种肩部疾病的发生有关。传统上，在肩部康复计划中，耸肩运动被用于通过加强上斜方肌来促进肩胛骨的上旋。本研究的目的是比较正常人群和病理人群在标准耸肩和上旋耸肩过程中的肌肉激活水平。
表面电极记录了23名正常参与者和14名多方向肩关节不稳定参与者的上斜方肌、中斜方肌、下斜方肌和前锯肌的肌电活动。参与者在肩关节外展0°时完成10次标准耸肩运动试验，并在冠状面肩关节外展30°时完成上旋耸肩运动试验。肌肉活动以最大自主等长收缩的百分比表示。
在改良耸肩过程中，所测试的四块肌肉的活动强度高于标准耸肩。在两组人群中，上斜方肌和下斜方肌的活动均显著增强（P < 0.05）。虽然对于中斜方肌和前锯肌，改良耸肩仅在正常人群中具有统计学意义，分别为P = 0.031和P = <0.001。
在正常人群和多方向不稳定人群中，上旋耸肩比标准耸肩更能有效地激发上、下斜方肌的肌肉活动。临床上，上旋耸肩可能有助于解决涉及肩部下垂和肩胛骨上旋减少的肩胛运动障碍。
